If an aircraft requests to takeoff, land, or touch-and-go on a closed or unsafe runway, inform the pilot the runway is closed or unsafe, and
If the pilot persists in his/her request, quote him/her the appropriate parts of the NOTAM applying to the runway and inform him/her that a clearance cannot be issued.
Then, if the pilot insists and in your opinion the intended operation would not adversely affect other traffic, inform him/her that the operation will be at his/her own risk.
RUNWAY (runway number) CLOSED/UNSAFE. If appropriate, (quote NOTAM information),
UNABLE TO ISSUE DEPARTURE/LANDING/TOUCH-AND-GO CLEARANCE.
DEPARTURE/LANDING/TOUCH-AND-GO WILL BE AT YOUR OWN RISK.
Except as permitted by para 4-8-7, Side-step Maneuver, where parallel runways are served by separate ILS systems and one of the runways is closed, the ILS associated with the closed runway should not be used for approaches unless not using the ILS would have an adverse impact on the operational efficiency of the airport.